Über die Reaktion von 2-Diazo-1,3-diketonen mit 1,3-ambident-nucleophilen Phosphor-Yliden: Eine neue Synthese von Monoheteroatom-Fünf- und -Sechsringen

✍ Scribed by Capuano, Lilly ;Drescher, Stefan ;Huch, Volker

• Publisher: John Wiley and Sons
• Year: 1991
• Tongue: English
• Weight: 390 KB
• Volume: 1991
• Category: Article
• ISSN: 0947-3440
• DOI: 10.1002/jlac.199119910157

✦ Synopsis

Reaction of 2‐Diazo‐1,3‐diketones with 1,3‐Ambident‐Nucleophilic Phosphorus Ylides: A New Synthesis of Monoheteroatomic Five‐ and Six‐Membered Rings

The thermolysis of 2‐diazo‐1,3‐diketones 1 with 1,3‐ambidentnucleophilic 3‐imino‐ 3, 3‐thioxo‐ 10 or 3‐oxophosphoanes 11 proceeds either by Wittig reaction, leading to the formation of the pyrrole 7 or thiophene nucleus 12, or competitively via a mechanism which involves both Wolff rearrangement and Wittig reaction by the acylcarbonyl, whereby 2‐pyridones 8, 2‐pyrones 14 or the indenyl acetophenone 15, respectively, are formed. The rates of these processes are strongly determined by substituent effects. As an exception to the general pattern of behavior, the cyclic acyl ketene derived from diazodimedone undergoes Wittig reaction with 3 through the ketene carbonyl, giving the quinoline derivative 9. The structure of 9 was confirmed by X‐ray diffraction analysis.